Protective underground shelter



Jan. 17, 1961 w. BASCOM 2,968,130

- 7 PROTECTIVE UNDERGROUND SHELTER I Filed Nov. 29, 1957 2 Sheets-Sheet 1 B Fig.l.

o o o o INVENTOR. wlllurd Buscom ZJAJW/ZILJ Jan. 17, 1961 w. BASCOM PROTECTIVE UNDERGROUND SHELTER Filed Nov. 29, 1957' 2 Sheets-Sheet 2 m O N 5 m mB m M W United States Patent PROTECTIVE UNDERGROUND SHELTER Willard Bascom, Washington, D.C., assignor to American Home Shelters, Berkeley, Calif., a firm Filed Nov. 29, 1957, Ser. No. 699,813

5 Claims. (Cl. 50-119) This invention relates to protective shelters primarily intended for human occupants. As will more fully hereinafter appear, the present shelter is designed more or less specifically to provide reason-able protection to human occupants against the thermal, blast, radioactive, and ground wave or earthquake effects produced by nuclear weapons.

It is an object of the present invention to provide that which may be conveniently termed a home or family type shelter having a seating capacity of perhaps eight persons and a sleeping capacity of perhaps four persons, such as two adults and two children. It is a further important aspect of the invention, and an important object thereof, to provide a shelter of the above type that can be purchased -and installed within the limits of the average family monetary budget.

The particular embodiment of the invention, which is illustrated in the drawings and which will be described hereinafter in greater detail, is shown as comprising a hollow plastic reinforced glass fiber shell, including a living area portion or chamber defined by substantially horizontal longitudinal base and ridge beams joined by outwardly bulged approximately parabolic arched opposite wall sections. One end of the chamber terminates in an upwardly inclined neck portion of progressively reduced cross-section, terminating in an entrance or hatch opening with a hinged door closure to permit ingress and egress by human occupants. The upper regions of the neck and the covered hatch opening extend substantially above the horizontal plane of the ridge beam of the chamber whereby the entire plastic shell may be buried beneath the surface of the earth a minimum of perhaps two to three feet, and with only the hatch opening and the upper part of the neck appearing above ground level.

In the preferred embodiments of the invention shown, a second batch or escape opening is provided adjacent the opposite end of the chamber. As will more fully appear, the shell may be excavated and buried in such manner that the second batch opening can be projected through a vertical retaining wall and into a separate escape passage; or the said second opening is such that it may be employed as a connecting passageway to join opposite ends of identically formed shelter units, whereby two units can be integrally connected together to serve as a single shelter unit with double the capacity of persons rated for one unit. I

A principal object of the invention is to provide a home shelter of the character hereinabove briefly mentioned which affords and provides a relatively high degree of protection against the eifects of nuclear explosions. In this connection, when the home shelter is installed by burying it beneath the surface of the earth with a minimum of two feet of earth over its shallowest part, and an average cover of over three feet of earth, such should provide quite satisfactory protection against even a very high level of radioactivity. It is also computed that the same shelter in the same type of installation would offer adequate protection to its occupants against blast pres- Patented Jan. 17, 1961 ICC sures of one atmosphere (15 psi.) or less. In the event it is possible to install the shelter with a preferred sixinch thick reinforced concrete slab interposed between the shelter and the ground surface, it is calculated that the blast pressure resistance would be doubled so as to safely withstand pressures up to two atmospheres (30 p.s.i.).

A feature of the shelter according to the invention is that it is preferably made in right and left-hand sections or segments which can be conveniently transported, stored, and handled prior to installation, and readily assembled either at the point of sale to the customer or at the actual situs of installation. This feature, coupled with the fact that the shelter with the occupant capacity above indicated, may be made within weight limits of from 250 to 400 pounds, permits the unit to be installed by a minimum labor force and at minimum expense.

Another feature of the invention is that the shelter being made of reinforced plastics can be designed, built, and decorated in such manner as to minimize as much as possible adverse psychological effects of the dismal and tomb-like atmosphere of more conventional reinforced concrete bomb shelters and the like. In this connection, the reinforced plastic material from which the shelter is made provides a greater feeling of warmth to both the touch as well as to the eye over concrete or steel structures. The reinforced plastic interior lends itself to be colored or decorated in any decor considered psychologically appropriate. I

A further object of the invention is to provide a shelter of the character above mentioned which may be rather inexpensively outfitted and furnished to provide both sleeping and sitting accommodations for its occupants. In this connection, it is contemplated and proposed that the interior outfitting and accommodations be generally equivalent to those which have been designed for cramped living quarters aboard small boats, ships, trailers and the like.

A further feature of the invention is that after it is once installed, the same would require substantially no care or maintenance in view of the fact that the plastic shell would be completely watertight and resistant to decay or rot.

Another object is to provide a reinforced plastic shelter in which the reinforcing beams and ribs may be made of integrally molded plastic material, and in which the lone gitudinal beams of the shelter also define abutting flanges between the two right and left-handed segments in which said flanges can be suitably apertured to receive bolts for securing the two segments firmly together.

A further feature of the invention is that the door for covering the primary or above ground-level opening may be provided with a conventional bellows-type ventilator for supplying air to the interior of the shelter. This outside connecting ventilator fitting, coupled with the fact that the plastic shell is adapted to be made with completely water and air tight seals, permits the entire shelter unit, after it is installed in the ground, to be vacuumtested to insure that the unit is capable of withstanding a predetermined minimum pressure of up to approximately one atmosphere. 1

A further object is to provide a unit in which the entrance passage, hatch opening and door closure therefor, may be made of minimum cross-section yet la ge enough to permit convenient passage of human o cupants therethrough. By reducing the cross-sectional areas of the passages, openings and doors, the area of direct radiation and blast is correspondingly reduced. The inclined neck or passageway of the unit in considerable mea"ure serves to baffle from the living area of the unit gamma rays which, for most practical purposes. can be considered as traveling in a substantially straight line path.

Another and more specific feature of the invention is to provide hinged doors or hatch covers over the openings in conjunction with a simple form of hand jack or other tool which will permit the doors to be mechanically pried and forced open from the interior of the shelter should such necessity arise by virtue of falling debris or the like weighting the doors closed.

Numerous other objects and advantages of the present invention will become apparent upon reading the following specification and referring to the accompanying drawings in which similar characters of reference represent corresponding parts in each of the several views.

In the drawings:

Fig. l is a longitudinal sectional view of a home shelter embodying the invention shown in installed position buried beneath the earths surface.

Fig. 2 is a perspective view showing portions cut away and in section of substantially the same installation indicated in Fig. 1.

Fig. 3 is a transverse sectional view of the shelter and showing in broken lines a seated human occupant therein.

Fig. 4 is a longitudinal sectional view of reduced scale, and showing two units embodying the invention positioned in adjacent end-to-end relation.

Fig. 5 is an enlarged fragmentary sectional view showing the application of a hand-jack to pry open one of the entrance doors from interiorly of the shelter.

Fig. 6 is a sectional view taken substantially on line 6-6 of Fig. 1.

Fig. 7 is a sectional view taken substantially on line 7-7 of Fig. 1.

Referring now more specifically to the drawings, the reinforced plastic shelter unit is indicated generally at A and is shown substantially completely buried in the earth B. In general, the unit A comprises a hollow shell including a living area portion or chamber 11, defined by substantially horizontal, reinforced plastic floor and ridge beams indicated at 12 and 13 respectively, and joined by outwardly bulged approximately parabolic arched side walls 14 and 16. One end of the chamber or living portion 11 terminates in an upwardly inclined neck 17 defining one of the entrance passageways to the area 11.

The upper end of the neck 17 terminates in a substantially circular hatch or entrance opening 18, fitted with a hatch cover or door 19, hinged as at 21, to the periphery of the neck opening 18. The upper regions of the neck 17, and the opening 18, project a substantial distance vertically above, as for example a minimum of two feet, the horizontal ridge beam 13 defining the chamber 11. As above noted, this permits a major portion of the unit, and particularly the entire chamber or living area 11 of the shell to be buried, a substantial distance beneath the surface of the earth B.

The second or opposite end of the chamber 11 terminates in an outwardly projecting reinforced nipple or passageway 22, also fitted with a hatch cover or door 23 hingedly mounted as at 24, to the outer periphery of passage 22.

The plastic shell unit above defined is preferably made in two right and left-hand segments specifically designated at A and A in the drawings. Each of the two segments is molded or otherwise formed with integral longitudinal flanges formed with spaced registering apertures adapted to receive securing bolts 26 orequivalent fastening means for joining the two half-sections together. More specifically, the half-segments A and A" are formed with complementary base or floor flanges such as shown at 12 and 12 depending exteriorly of the shell unit. Said segments are also formed with matching pairs of upper ridge defining flanges fil -13 and 13 -13 The flanges 13 13 project upwardly exteriorly of the plastic shell whereas said flanges 1313 project downwardly and reentrantly into the interior of said shell. To secure an absolutely moisture-proof seal, a suitable sealing com- 4 pound or mastic may be interposed between the matching flanges when these parts are bolted or otherwise fastened securely together. It is further appreciated that the above mentioned flanges define in effect the floor and ridge beams for the unit heretofore indicated generally at 12 and 13.

Each of the reinforced plastic segments A and A" are further formed with spaced transverse molded reinforcing ribs 27 to provide desired transverse strength and rigidity for the shell unit.

The materials from which each half A and A" of the shell unit may be made and the method of molding or otherwise fabricating the parts is considered to be matters well within the skill of the reinforced plastics art. By way of example, however, it is proposed that a satisfactory shell unit may be fabricated from polyester resin reinforced glass fiber cloth and/or glass fiber matte in suflicient plies to provide approximately a one-quarter inch wall thickness. Generally speaking, the materials used in the methods of fabrication may be substantially identical or parallel to the practices known and followed in the present-day manufacture of reinforced plastic boat hulls, automobile bodies, and similar applications.

The interior of the shell may be outfitted in accordance with eflicient utilization of living and storage space to provide maximum comfort to the occupants. In the drawings there is disclosed how the living chamber 11 may be provided with cupboard storage lockers 28 and 29, defining bench seats and a walkway 31 between them. One of the lockers 29 may be formed with a hinged leaf 32 that can be swung upwardly across passageway 31 to provide a substantially continuous flat bed surface extending across the widest part of the shell for sleeping purposes.

In addition to the locker bench seats above mentioned, the shelter as illustrated in the drawings is further shown as being outfitted with a battery-operated lamp 36 for interior lighting, an outside extensible radio antenna 37, and a multiple-rung ladder 38 located in the lower regions of the neck portion to facilitate ingress and egress of occupants through passage 17. It is appreciated, of course, that lockers 28 and 29 can be utilized to store food, water, sanitary equipment, first aid supplies, blankets, books, amusement devices and other items which the occupants may desire to have readily on hand.

To provide air ventilation to the interior of the shelter at hand operated bellows unit, including a bellows portion 39 and an operating handle 41, normally latched in an operative position by keeper 42, is mounted on the inside of door or hatch cover 17. Operation of the bellows in conventional fashion is adapted to suck air through one or more apertures 43 in door 17 and discharge and circulate said air through ports 44 of the bellows. It is contemplated, of course, that during relatively long waiting periods within the shelter, particularly when the occupants might anticipate even a minute or two advance warnings prior to actual attack or explosion, either one or both of the hatch covers 17 and 23 would be left open to secure natural draft ventilation through the unit.

As previously indicated, by providing hatch cover 19 (which is substantially the only part of the unit adapted to be located above ground level) with ventilator opening 43, it is possible to connect a conventional vacuum testing unit (not shown) exteriorly of the door at said opening 43 by evacuating air from the shell A and test its ability to withstand blast pressure up to at least about one atmosphere. The value of being able to easily test the shelter at its actual situs of installation is believed apparent.

Figs. 1, 2 and 3 illustrate one satisfactory and preferred form in which the plastic shell A may be installed underground. More specifically, the unit is shown as being buried beneath the earths surface to a depth whereat a minimum of 24 inches of tamped or packed earth covers the top ridge beam 13 of chamber 11. Only the v extreme upper regions of the neck 17 and the door covered hatch opening 18 are located above the ground surface.

As previously indicated, it is preferable to interpose a reinforced concrete slab 48, preferably at least coextensive in length and width to the length and width of chamber 11 of the shell, between the ground buried chamber 11 and ground surface. It is estimated that the provision of a reinforced concrete slab of about six inches in thickness would enable the plastic shell to withstand blast pressures up to at least two atmospheres.

In the arrangement shown in Fig. 1, the entrance passage 22 is projected through a reinforced concrete retaining wall 49 which, for purposes of illustration, may be assumed to open into the basement or other subterranean level of the house or home to which the shelter is annexed.

Reference numeral 51 indicates a ground anchor which may comprise a flat section of metal (as shown) or a flat section of reinforced concrete connected by a chain or cable 52 to fitting 53 bolted to the underside of the shell unit A. The purpose of the ground anchor 51 is to prevent flotation of the relatively buoyant shell A in relatively wet or muddy ground locations. It is noted that the effectiveness of the ground anchor 51 to prevent flotation of the shell does not depend in largest measure upon the weight or gravity pull of the element 51, but depends in much greater degree on the fact that the relatively large flat upper surface 51 of the anchor element 51 will create tremendous resistance to direct vertical upward pull or movement through the packed earth in which it is interred.

Fig. 4 discloses an installation of two identically formed reinforced plastic shelter units A arranged in end-to-end relation with the two abutting passageways 22 defining a communicating passage between the two units. It is appreciated that if the units are installed in this fashion, the doors 23 would be removed from each of the passages 22 and that suitable precautions would be taken to form a completely tight and waterproof seal between the adjoining passages 22. Alternatively, it is contemplated that two of the units A might be arranged in substantially identical fashion as shown in Fig. 4, but with the doors 23 on each unit left on and with only a speaking tube (not shown) communication established between the said two adjoining units A. This latter installation and numerous other modified installations are considered matters well within the skill of the art and further detailed explanation or amplification thereof is considered as being unnecessary for the proper understanding and appreciation of the versatility in installation and use of one or more units of the subject type.

In order to minimize as much as possible the danger of occupants becoming trapped in the shelter unit due to debris falling and piling up on or against the hatch covers 19 or 23, I provide a simple ratchet type handactuated jack 60, which can be operated from interiorly of the shell to forcefully pry open either of the doors 19 or 23 to facilitate escape. More specifically, and referring particularly to Fig. 5, the jack is shown as comprising a ratchet bar 61 fitted with a shoe 62, and including a conventional lever 63 actuated pawl type mechanism 64 operable to move the shoe forcefully and progressively along the length of the ratchet bar 61. The shoe 62 is provided with a hook 66 engageable in a preformed notch 67 molded in the plastic shell adjacent the unhinged side of each of the doors 19 and 23. As

indicated in Fig. 5, when the hook 67 is engaged within notch 66 and the handle 63 is oscillated back and forth in conventional fashion, the bearing pad 68 on the ratchet bar will be forcefully urged against the inside face of the door to pry the latter open against any external force tending to maintain it shut.

It is appreciated that by making the cross-section of the living area portion or chamber 11 of the plastic shell lower regions of the shell interior optimum living space 3 in ratio to the total cubic foot capacity of the unit can be achieved, while, at the same time, the parabolicarched structure inherently defines a shell adapted to withstand external hydraulic pressures, such as blast pressure, tending to collapse the unit.

It is also apparent that by fabricating the shell unit' initially in complementary right and left hand segments, it is possible to outfit the interior of the half shells, with the larger items such as storage lockers and, the like prior to assembly of the two segments together, whereby it is possible to avoid having to design the interior fittings small enough to be accommodated through either of the entrance passageways 17 or 22.

Although the present invention has been described in some detail by way of illustration and example for purposes of understanding, it is understood that numerous other changes and modifications may be practiced within the spirit of the invention as limited only by the scope of the claims appended hereto.

I claim:

1. A protective shelter for human occupants comprising in assembled condition a hollow reinforced plastic shell including a living area portion and a neck portion comprising: an elongated horizontal chamber defined by uninterrupted floor and ridge beams joined by outwardly bulged wall sections; one end of said chamber termi nating in an upwardly inclined neck portion of reduced cross-section terminating at its upper end in a hatch opening; said shell formed from two complementary right and left-hand longitudinal half-sections each defining one-half of the chamber and one-half of the upwardly inclined neck portion; the longitudinal margins of said halfsections defined by continuous complementary abutment flanges mutually abutted and rigidly joined together in assembled condition of the shell; said abutting and rigid ly joined flanges defining said floor and ridge beams of said shell.

2. The combination of claim 1 and wherein said chamber term nates at its second end in an outwardly projecting hollow nipple of reinforced plastic defining a second hatch opening and passageway communicating to the interior of said chamber; each said half-section defining as an integral part thereof one-half of said nipple and the opening and passageway defined thereby.

3. A protective shelter comprising: a pair of outwardly bulged approximately parabolic arched wall sections formed of reinforced plastic each having an upper and a lower continuous flange coextensive with the length thereof; the upper flanges and the lower flanges, respectively, of the sections being arranged in fixed abutment thereby defining a hollow shell including a chamber portion and a neck portion having uninterrupted floor and ridge beams; the chamber portion terminating in an upwardly inclined neck portion of reduced cross-section terminating at its upper end in a hatch opening; the upper portions of said neck and said hatch opening extending substantially above the plane of that length of the ridge beam along said chamber portion.

4. A protective shelter for human occupants comprising a hollow shell made of reinforced plastic having uninterrupted fioor and ridge beams including a living area portion and a neck portion comprising: an elongated chamber defined by a pair of outwardly bulged wall sections; one end of said chamber terminating in an upwardly inclined neck portion of reduced cross-section terminating at its upper end in a hatch opening; said shell formed from two complementary right and left-hand longitudinal half-sections each defining one-half of the chamber and one-half of the upwardly inclined neck portion; each of said half-sections having a continuous floor flange and a continuous ridge flange member; said half-sections being held together by means of complementary abutment of the fioor flanges and the ridge flange members, each of said members comprising an upwardly projecting flange. and a downwardly projecting 5 flange, said upwardly projecting flange being continuous along the entire length of said shell and said downwardly projecting flange being continuous along the entire length of said chamber; said abutting floor flanges and said abutting ridge flange members defining floor and ridge beams, respectively, of said shell.

5. A protective shelter as defined in claim 4 wherein said plastic comprises resin and glass fiber.

References Cited in the file of this patent UNITED STATES PATENTS 503,689 Walker Aug. 22, 1893 1,049,543 Smith Jan. 7, 1913 2,629,348 Kifferstein Feb. 24, 1953 OTHER REFERENCES Civilian Defense Protective Construction, Structures Series Bulletin No. 1, issued by the Division of State and Local Cooperation Office of Emergency Manage ment, 1941, pages 24-27, 31-34 (face page 36, Nos. 2, 3, 6).

American Builder, page 198 relied on, August 1955. 

